This study is designed to compare the pharmacokinetics and effects of bupre-norphine following administration of the sublingual tablet formulation over a dose range of 4 to 24mg. This open label study will include twelve subjects at two sites; New England Medical Center/Tufts and Universuty of Cincinati. The subjects will be male/female. age 21-45, within 15% of ideal body weight and use opiates. Each hospitalized patient will receive ascending single doses of 4,8, 16,&24mg buprenorphine with a 10 day interval between doses.